Allergic purpura is a hemorrhagic disease caused by the body’s allergy to a substance that leads to damage of small blood vessels throughout the body, and bleeding can occur in the skin, mucous membranes, joint cavities or internal organs. The disease can occur at any age, but it is more common in children and adolescents, more in boys than in girls. The disease occurs throughout the year, mostly in spring and autumn.
Etiology
The cause is not yet clear, and is related to infection, food, drugs and other factors.
1, infection: 50% to 90% of children have a history of upper whistle infection before the onset of the disease.
2, food: protein foods such as meat, milk, eggs, seafood, soy products, etc. may be triggering factors.
3, drugs: antibiotics, biological agents, plasma, blood products, vaccinations, etc.
4, biological: bacteria, viruses, parasites, animal bites, mosquito stings, etc.
5, seasonal changes: cold, high temperature intolerance, etc.
6, certain foreign substances: such as dust mites, pollen, willow, cosmetics, animal fur, home decorating odor, chemical fibers in contact with the skin may trigger allergies.
[Pathogenesis].
The pathogenesis is not yet clear, but may be due to the action of various irritants, including infectious agents and allergens, on individuals with a genetic background, stimulating allergic reactions and/or the formation of antigen-antibody complexes, causing immune damage to blood vessels, resulting in increased capillary permeability and fragility and small vessel vasculitis,
Gastrointestinal tract, joints, kidneys, etc. can be damaged.
Clinical symptoms
The symptoms can last from a few days to a few weeks, mainly in the skin, joints, gastrointestinal tract, kidneys and other organs, and are classified into four types according to their clinical manifestations: simple skin type, joint type, abdominal type and renal type. Among them, simple skin type is the most common, with recurrent skin purpura as the main manifestation, mostly petechiae or petechiae of pinpoint to soybean size, which can be high on the skin surface, and some have the tendency to fuse. The buttocks and both lower extremities are most frequently involved. The renal type purpura, also known as purpura nephritis, is the most serious complication of allergic purpura, mostly seen in teenagers, renal damage can occur simultaneously with purpura or before and after purpura, hematuria is the most common, can be accompanied by proteinuria, the duration of the disease varies, usually weeks to months, the presence or absence of renal lesions directly affect the prognosis, in general, children with purpura nephritis have a good prognosis, but very few can develop end-stage renal failure.
Treatment】
1, general therapy The acute phase should be bed rest, after the symptoms reduce or disappear can gradually increase the amount of exercise. At the same time actively search and remove the causative factors, diet should be free of light, appropriate vitamin supplementation, if necessary, animal protein can be prohibited. If you have gastrointestinal symptoms, give semi-liquid or liquid diet or even fasting according to the situation.
2. Give antispasmodics such as 654-2 and H2 receptor antagonists such as cimetidine to those with gastrointestinal tract.
3.Anti-allergic treatment, such as loratadine, cetirizine, xylazine, paracetamol, etc.
4.Reducing vascular permeability: rutin, vitamin C, anorectic blood, etc.
5.Anticoagulation: Pansentin, heparin, etc.
6.Glucocorticoid: if the rash is severe, or with obvious abdominal pain, or with obvious kidney damage, hormones can be applied for a short time.
7, immunosuppressant: severe allergic purpura, purpura nephritis can be added with immunosuppressant, such as cyclophosphamide, leigandine polyglucoside tablets and other drugs.
8, identification and treatment, Chinese medicine with Western medicine is certainly effective.
Prognosis]
The disease generally improves within 6-8 weeks, most of the prognosis is good, some cases can be recurrent for several years. In those with renal involvement, the course of the disease is relatively long, and a few may develop into chronic nephritis, and very few may have a poor prognosis due to renal failure. A few children with severe disease may die due to intestinal bleeding, intussusception, intestinal necrosis, and intestinal perforation.